What does it mean when a name is in Red with an! In iMessage?

This guy I work with and I been flirting since July 5. He has a iPhone and when I try to send him a iMessage through my iPod touch it says his name in red with a! Does that means he turned off his iMessage?

Nope! This means it not correctly sending. Try again by clicking on it. There's no solution really but if it continues turn it off and back on! Hope i helped

Usually means that they either aren't signed up or don't have it connected.